Slab Leak: Signs Under the Foundation You Shouldn’t Ignore
Water under a slab rarely fixes itself
A slab leak is a pressurized supply (or sometimes hydronic) line leaking under or in a concrete foundation. Left alone, it can waste water, undermine soils, and damage flooring. This page is only about slab-leak intent—not general faucet drips.
Suspect a slab leak? Call (844) 936-0420 to connect with a local plumbing professional when available.
Referral and education—not a foundation company. No fabricated “we’ve repaired 50,000 slabs” claims.
Common signs (not a self-diagnosis)
- Unexplained spike in the water bill
- Sound of running water when fixtures are off
- Warm spots on the floor (hot-line leak)
- Persistent wet carpet, baseboards, or flooring with no upstairs source
- Cracks that appear or grow with moisture patterns (many crack causes exist—don’t assume)
- Low pressure combined with meter movement at zero use—see also low water pressure
- Musty odors from under flooring
First checks
- Confirm no fixtures, softeners, or irrigation are running.
- Read your water meter, wait 15–30 minutes without use, and check for movement (where accessible and readable).
- Shut the main and see if the sound/meter stops—helps separate supply-side leaks from other issues; know your shutoff.
- Avoid tearing up flooring blindly; professional location saves damage.
If water is actively pooling near electrical equipment, prioritize safety and emergency escalation.
Why specialized detection matters
Pros may use acoustic listening, thermal imaging, pressure tests, or tracer methods to locate lines before cutting concrete. Ask about detection fees, repair options (spot repair vs. re-pipe), and how flooring/restoration is handled—often separate trades.
Broader non-slab moisture issues belong on leak detection. Active spraying lines may overlap burst pipe response.
Related guides
FAQ
Are all foundation moisture problems slab leaks?
No—condensation, drainage, sewer leaks, and weather intrusion differ. Detection sorts causes.
Will you quote slab repair online?
No. Access, pipe type, and finish repairs vary widely. Ask for on-site clarity.
Connect with a local pro
Guides by city
Same topic with local context for homeowners in these metros. Coverage still varies by time and location—these are guides, not local offices.
- Albuquerque
- Atlanta
- Austin
- Baltimore
- Boise
- Charlotte
- Chicago
- Cincinnati
- Cleveland
- Colorado Springs
- Columbus
- Dallas
- Denver
- Des Moines
- Fort Collins
- Fort Worth
- Fresno
- Grand Rapids
- Greensboro
- Indianapolis
- Irvine
- Jacksonville
- Kansas City
- Las Vegas
- Long Beach
- Los Angeles
- Louisville
- Memphis
- Miami
- Milwaukee
- Minneapolis
- Nashville
- Oklahoma City
- Omaha
- Orlando
- Phoenix
- Portland
- Raleigh
- Richmond
- Riverside
- Sacramento
- Salt Lake City
- San Antonio
- San Diego
- San Jose
- Seattle
- Spokane
- Tampa
- Tucson
- Virginia Beach
Or start from a metro router: All location hubs.